In a motor control device as a conventional power conversion device, an AC power supply is rectified by a rectification circuit unit, and a high-power-factor converter circuit unit steps up inputted DC voltage and outputs the resultant voltage. The high-power-factor converter circuit unit controls the time ratio of ON and OFF of a switching transistor in a sinewave manner, thereby improving the power factor, and controls the DC voltage. The stepped-up DC voltage is stabilized by a smoothing capacitor, and an inverter circuit unit converts the DC voltage supplied from the smoothing capacitor, to three-phase AC, and supplies the resultant voltage to a motor, to drive the motor. In the case where the smoothing capacitor has a small capacitance, if, in particular, the commercial AC power supply is a single-phase type, ripple voltage of DC bus voltage, which varies at a frequency twice as high as the power supply frequency, increases.
The voltage applied to the motor varies due to the ripple voltage of the DC bus voltage, whereby the motor phase current pulsates. In order to remove the pulsation, a control unit outputs, to the inverter circuit unit, a voltage pulse corrected so as not to be influenced by the DC bus ripple voltage, by applying, to DC bus voltage, a feedback value of DC bus voltage detected by DC bus voltage detection means when calculating a current command, and thus drives the motor (see, for example, Patent Document 1).